CHICAGO — Chicago’s police superintendent has called for the firing of seven officers for their response to a colleague’s fatal shooting of Laquan McDonald in 2014, a case that roiled the city and laid bare longstanding tensions between the police and black Chicagoans.

The dashboard camera video of the shooting that was released, under public pressure, in November incited widespread protests and exposed an entrenched “code of silence” among officers who had sworn to a far different account of the shooting from what the video captured.

The case has led to increased scrutiny and skepticism of the department, including a Justice Department investigation into Chicago police practices and the firing of the previous police superintendent last year as protests intensified. Mayor Rahm Emanuel remains under pressure to provide more transparency and overhaul the police disciplinary system.

The call to fire the officers broadened the departmental fallout as the force struggles to restore public trust.

The seven officers recommended for firing were accused of making false reports. They had backed up Officer Van Dyke’s account that Mr. McDonald had moved menacingly toward him with a knife. But their story was contradicted by the video of the shooting; while Mr. McDonald had a knife, he seemed to be veering away from the police when Officer Van Dyke shot him, and the gunfire continued after the teenager collapsed to the ground.

Officer Van Dyke, the only officer who fired his gun that night, has been charged with murder and is awaiting trial. He has pleaded not guilty and said he feared for his life.

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Laquan McDonald, right, moments before he was shot and killed by Officer Jason Van Dyke in Chicago in October 2014.CreditChicago Police Department

To the department’s critics, the significance of the video of Mr. McDonald’s shooting was not just in showing how wanton and unnecessary his killing had been, but in starkly demonstrating how blatantly and casually police officers had lied about the circumstances of another officer shooting a man. Such “code of silence” cover-ups of misconduct, critics said, had rarely been made so plain as in the discrepancy between the officers’ accounts of the killing and what the video later showed.

Craig B. Futterman, a University of Chicago law professor who directs a civil rights and police accountability project at the law school, said the move to fire the officers was a start.

“This is an important and necessary step,” he said. “But it can’t be a one-off. It has to be a consistent practice that if you lie, you are fired. The sad fact is that lying has become a regular and entrenched practice when police misconduct occurs, and disciplining or firing officers for engaging in that practice has rarely happened.”

In an email to Chicago police employees announcing his decision, Superintendent Johnson said he believed “that through these challenges we can take the lessons learned to become a better department.”

“While I know that this type of action can come with many questions and varying opinions, please know that these decisions were not made lightly,” he said. “Each of these decisions was based on a methodical and substantive review of the facts by both internal and external counsel. Each officer will have their right to due process.”

Mr. Emanuel said in a statement that he supported the superintendent’s decision.

“As the city takes these important steps to hold individuals accountable, we must also recommit ourselves to partnering together to rebuild trust between our police department and our residents,” Mr. Emanuel said.

The president of the union representing rank-and-file officers did not immediately respond to messages on Thursday seeking comment.

Mr. Futterman said the discipline should not stop with the rank-and-file.

“The code of silence goes far higher than that, and goes far higher in this case,” Mr. Futterman said. “It’s even more important that those at top of the food chain are held accountable.”

He said it remained to be seen whether the department’s response is unique to the highly scrutinized McDonald case — or whether it signals that lying to investigators to protect another officer’s misconduct will no longer be tolerated.

With African-Americans making up one third of the city, the question is critical to the department and the city. Public hearings this summer on the Justice Department’s investigation revealed deep rifts, as frustrated and angry minorities recounted tales of victimization.

But many said getting dangerous and abusive police officers off the streets was only part of the issue. Equally significant, residents said, was fixing a broken, or nonexistent, disciplinary system so it would bring accountability after cases of police abuse.

The seven officers Superintendent Johnson recommended firing were made to turn in their badges until the Police Board made its decision. But he cannot terminate them unilaterally. The officers, who were not named, will have a chance to contest the action before the city’s Police Board, whose members are appointed by Mr. Emanuel.

The Police Board’s executive director, Max A. Caproni, said Thursday that his office had not yet received formal charges against the officers. Once those charges are filed, the officers will have the option to hire lawyers and contest the findings.

The disciplinary process can take months to play out. Mr. Caproni said the median time for a hearing was about four months after charges are filed, and the median time for a disciplinary decision was about seven months.

Without any lawsuit being filed, and long before criminal charges were filed and the video was made public, Chicago’s City Council approved a $5 million settlement for Mr. McDonald’s family. But his death is just one of several noteworthy police shootings here in recent years. Since 2004, Chicago has spent more than $500 million to settle cases of alleged police misconduct.

Those payments, which have come as Chicago has struggled to fund its school system and meet its pension obligations, have frustrated residents. During protests last year after Officer Van Dyke was charged, demonstrators repeatedly chanted “16 shots and a cover-up,” and many urged Mr. Emanuel to resign.

The Department of Justice investigation includes an examination of how the Chicago police treat minorities and punish misconduct in its ranks. It could eventually lead to a legally binding agreement with the city imposing significant changes in how the police operate.

The City Council has also been holding hearings on the creation of a new agency to investigate police abuses; community activists are waiting to see whether the proposal by the mayor and his Council allies has real teeth and independence, or whether the structure of the new agency would be as ineffective as the existing police review authority that it would replace.

In the aftermath of the McDonald case, the city’s inspector general issued a report recommending the firing of eight officers, said Anthony Guglielmi, a police spokesman. The department “respectfully disagrees” with the recommendation to fire the eighth officer, Mr. Guglielmi said in an email, “and feels that there is insufficient evidence to prove those respective allegations.”

Two other officers cited by the inspector general have since retired, Mr. Guglielmi said. The inspector general’s report has not been published.

Mr. Guglielmi also said the officers’ names would not be released until formal charges were filed with the Police Board. Both the Police Department and the Office of Inspector General said they could not release the report recommending the firings or Superintendent Johnson’s response.

Federal investigators said they were also investigating Mr. McDonald’s shooting, and a special prosecutor has been appointed in state court to investigate whether officers who witnessed the shooting committed crimes.

Mitch Smith reported from Chicago, and Richard A. Oppel Jr. from New York.

A version of this article appears in print on , on Page A10 of the New York edition with the headline: Chicago Officers Face Firing in Police Shooting Cover-Up. Order Reprints | Today’s Paper | Subscribe